What does "Distribute as needed" on chef dudes mean? On earlier levels when I can pay attention to individual dudes I notice there are hamburgers waiting even when dudes aren't at full health. When does the healing actually occur?

What is the mechanic behind "distribute as needed"? It doesn't appear to mean "until everybody is at full health." I am especially curious because I had an annoying anti-synergy run with explorer dudes and ghost dudes where explorer dudes won't heal up much past 30%, and Ghost dudes only redistribute to even health... so it caused all dudes to work their way down to max 50% health, then once all were at 50%, then work their way down to max 30% health. So if I am going to pair a healer with Ghost Dudes I want to make sure they can actually heal up past 50%.